This invention relates to a mold closing unit which forms part of an injection molding machine and which has a mold changing device, a conditioning table as well as a supply line coupling which includes coupling halves that may be separated and joined along a horizontal parting plane for coupling flexible supply conduits of an injection mold assembly to supply conduits at the machine side of the form closing unit for the purpose of preheating (conditioning) the injection mold on the conditioning table from which the injection mold assembly--without removal of the supply conduits--may be conveyed horizontally and perpendicularly to the closing device of the form closing unit into its working position in the mold clamping chamber of the mold closing unit. The mold-side coupling half is affixed to the mold body in front of the rear end face thereof. The rear end face is oriented away from the clamping space of the mold closing unit, and the mold body of the injection mold assembly is bounded by back plates. The machine-side coupling half is movably arranged between the conditioning table and the mold clamping space.
By "conditioning" there is meant the thermal adaptation of the injection mold assembly to the intended operational conditions. Such conditioning is performed externally of the working position and, as a rule, it occurs during the injection molding operation performed with another injection mold assembly.
According to a known mold closing unit with associated injection mold changing device, disclosed, for example, in German Pat. No. 3,323,353, to which corresponds U.S. Pat. No. 4,518,338, the supply line coupling is designed for an injection mold assembly which is placed onto the conditioning table by lowering in a vertically downward direction. The vertical positioning motion is utilized for the mutual approach motion of the coupling heads or coupling halves to achieve mutual contacting thereof and is thus also instrumental for coupling the supply conduits. The machine-side coupling head is connected with the conditioning table by means of a coupling rod which is displaceably supported in a guide of the conditioning table and which is moved with the injection mold assembly into the clamping space of the mold closing unit. The mold-side coupling head is connected by means of a connecting piece with the injection mold assembly standing on the conditioning table such that the mold-side coupling head remains at all times in the same spatial relationship relative to the conditioning table. In case of mold bodies of different dimensions, this unchanging relationship is achieved by using a connecting member of complemental dimensions. This ensures that during the vertical setting motion of the injection mold assembly, the line terminal couplings of both coupling heads are at all times in alignment (flush) with one another in the vertical direction.
It is further known, as disclosed, for example, in German Offenlegungsschrift (Non-examined Published patent application) No. 2,332,205, or European patent application No. 92,868 to provide injection mold assemblies with back plates which project frontally beyond both sides of the rectangular mold body.